A common flushing apparatus for toilets involves a reseating flush valve that holds a large volume of supply water in a tank from which it is suddenly released into the toilet bowl. And, a float valve is responsive to the water level in the tank to replace the water level, operating automatically and separately from the flush valve that is manually operated by movement of a flush handle or lever that is turned to lift the flush valve. A detrimental feature of this common system is that the flush valve tends to and eventually leaks, resulting in continued water waste.
Another flushing apparatus, common in the United Kingdom, involves a syphon tube having its suction leg depending into the supply tank so as to be filled with water, and its discharge leg normally empty of water and opening into the toilet bowl, and operated by means of a primer pump that is manually actuated to fill the discharge leg thereby initiating syphoning. The said primer pump operates as a water lifting means in the suction leg of the syphon, and the advantage of this syphon system is that there can be no leakage from the supply tank through the inactive syphon. However, the pump means gradually deteriorates and requires repeated cycles of operation in order to complete a flushing of the toilet, and eventually becomes inoperative.
In view of the foregoing, it is an object of this invention to employ the aforesaid syphon tube flush principle of operation to the exclusion of pump means, and replacing the aforesaid pump-type primer means with a syphon primer means activated by opening of the flush valve, all in combination with an otherwise conventional toilet.
The syphon principle of operation is superior with respect to the conservation of water, in that there can be no continuous leakage therethrough when its discharge leg is empty of water. And, only when the discharge leg is primed does water flow therethrough. On the contrary, the conventional flush valve principle of operation is prone to continuous leakage from the water supply tank and through the flush tube, due to deterioration of either the valve seat or valve ball. It becomes apparent therefore that the syphon principle is superior, except for the inevitable deterioration of the United Kingdom type pump means thereof which typically deteriorates and requires repeated cycles of operation in order to complete a flushing of the toilet, and inevitably becomes inoperative.
In view of the foregoing, it is an object of this invention to employ the aforesaid syphon tube flush principle of operation to the exclusion of a pump means, and replacing the aforesaid pump-type primer means with a pre-primer means operable by opening the flush valve, and all in combination with an otherwise conventional toilet.
It becomes apparent therefore that the United Kingdom syphon principle is superior, except for the inevitable deterioration of the pump means thereof which is typically a flap or disc of flexible material that lifts the tank water into the syphon and initiates continued flow therethrough until the water supply tank is emptied through the flush tube. Accordingly, these two widely used principles of operation are each subject to deficiencies, one to inherent leakage and the other to eventual inoperation. In view of the foregoing, it is an object of this invention to provide a toilet flushing apparatus that virtually eliminates leakage of the flush water, and that provides automatic refilling of a primer tank for repeated flushings.
It is to be understood that the water supply tank is refilled after each flushing operation, or incomplete flushing operation, by means of a conventional and accepted water level responsive valve means from a water supply service pipe. In practice, a float controlled valve returns the tank water level to the bridge of the syphon after each flushing operation, complete or incomplete. And, it is this maintained water level that automatically refills the primer tank.
The syphon principle of operation is characterized by two conditions, a passive condition wherein the discharge leg is closed to the flush pipe by the flush valve and the primer tank is in open communication with and to fill the discharge leg with water up to the syphon bridge coincidental with the supply tank water level and with a transfer passage over the bridge and between the two syphon legs being empty and vented to atmosphere, and a functioning condition wherein the discharge leg is opened to the flush pipe by lifting the flush valve, a float, and opening the primer tank for discharge of its primer water over a jet opening of the discharge leg and into the flush pipe and inherently closing the atmosphere vent to said transfer chamber.
The flush valve closes the discharge leg below the bottom opening of the primer tank, the bottoms of the primer tank and discharge leg being separated by the jet opening and in open communication. In order to achieve said functioning condition, priming of the syphon is required for filling the otherwise empty transfer passage with water, whereupon syphoning action is initiated and continues to occur. It is an object of this invention to initiate syphoning by pre-priming the transfer passage with a small volume of water through the suction leg of the syphon and thereby initiate the syphon effect. That is, by flooding the two syphon legs and thereby enabling the syphon function.
The apparatus herein disclosed is characterized by a manually activated primer means in the form of a primer tank that dumps water over a jet opening and into the flush tube, and which simultaneously draws water over the syphon bridge for priming the syphon. The atmospheric closure of the transfer passage in the flush mode is a prerequisite to successful flushing, and to this end it is an object of this invention to provide vent control means by which the transfer passage is closed to atmosphere in the flush mode, said vent being open to atmosphere in the passive mode in order to enable filling of the two syphon legs.
In the preferred embodiment of this invention, the flush valve is positioned at the bottom of the syphon discharge leg in open communication with both the discharge leg and primer tank water, both legs of the syphon being primed when the storage tank water level is automatically replenished. In practice, operation is restored by simply re-filling the primer tank, and repair is by cleaning or replacement of the valve seat or flush valve. Accordingly, it is an object of this invention to prevent closure of the syphon when the primer tank water is depleted, and to this ends means is provided to ensure flotation of the flush valve during flow of water from the bottom of the syphon discharge leg, all of which is accomplished by upward reaction of water thrust against the flush valve, as will be described.